Sitka Spruce top crack

Wood choice logic, brace shapes, braces patterns -- what and why for the "heart of the guitar"
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Ray Ussery
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Sitka Spruce top crack

Post by Ray Ussery » Thu Dec 20, 2012 11:43 am

I was thinning out the top and when finished found a crack in the joint at the heel end about a 1/2 inch long.
Best way to repair?

Thanks, Ray

John Parchem
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Re: Sitka Spruce top crack

Post by John Parchem » Thu Dec 20, 2012 3:01 pm

Is the joint separating or is there a crack in the wood? I have not seen any pictures of the top but I am wondering if it is already profiled; are there braces glued on?. I found it hard to repair a failed top or back glue joint with more glue as the glue is just bonding to glue. If it is not profiled I would separate the halves and rejoin them. If the top is already profiled I would consider a new top.

ken cierp
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Re: Sitka Spruce top crack

Post by ken cierp » Thu Dec 20, 2012 3:52 pm

Ditto John ---- the void needs to be filled with a sliver of "with the grain" spruce. Seems this top was joined when is was not dry enough for ude or the RH was over 45%.

Ray Ussery
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Re: Sitka Spruce top crack

Post by Ray Ussery » Thu Dec 20, 2012 10:47 pm

Yes I believe it was glued up when the humidity was high...I actually got down to business and looked at it carefully with a good magnifier and it isn't in the joint after all...the crack is following a grain line about an 1/8Th of an inch from the joint.

It was profiled if you want to call it that...the braces were flat and starved for glue..I removed them and took about .020 off and it now measures .098 pretty much all over and it's still stiff...

The crack would be under the fingerboard extension when completed. The crack fits perfectly if you didn't know it was there you wouldn't see it at all.

Ray

John Parchem
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Re: Sitka Spruce top crack

Post by John Parchem » Thu Dec 20, 2012 11:07 pm

If it is under the finger board I would just leave it alone. The fingerboard will make a good patch.

TonyinNYC
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Re: Sitka Spruce top crack

Post by TonyinNYC » Fri Dec 21, 2012 11:17 am

And since it is not glued, you could try to work some glue into the crack for insurance. But, since that part of the soundboard, if I am understanding its location correctly, will also be glued to the neck block so it should be fine.

Ray Ussery
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Re: Sitka Spruce top crack

Post by Ray Ussery » Fri Dec 21, 2012 11:49 pm

Thanks Fellas!

Ray

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